We face a similar problem, connecting database fields to GUI widgets.
We came up with a concept of a "tied reference" variable.  Included
below is the interface - you can probably work out how it works.  It
has to be said that it wasn't particularly successful, and still
required lots of manual and repetitive work to make it happen.
Luckily we ditched that project for financial reasons :-)

Rich.

------------------------------------------------------------ tiedref.mli
(* Tied references.
 * Copyright (C) 2003 Merjis Ltd.
 * $Id: tiedref.mli,v 1.2 2003/12/02 13:22:01 rich Exp $
 *)

type 'a tiedref

val tiedref : read:(unit -> 'a) -> write:('a -> unit) -> 'a tiedref

val ( !* ) : 'a tiedref -> 'a
val ( *:= ) : 'a tiedref -> 'a -> unit

------------------------------------------------------------ dbtiedref.mli
(* Database-backed tied references.
 * Copyright (C) 2003 Merjis Ltd.
 * $Id: dbtiedref.mli,v 1.3 2004/03/08 13:44:25 rich Exp $
 *)

open Tiedref

type dbrow

val dbrow : Dbi.connection -> string -> string -> Dbi.sql_t list -> dbrow

type 'a dbfield

val dbfield_bool_not_null : string -> bool dbfield
val dbfield_bool : string -> bool option dbfield
val dbfield_int_not_null : string -> int dbfield
val dbfield_int : string -> int option dbfield
val dbfield_string_not_null : string -> string dbfield
val dbfield_string : string -> string option dbfield

val dbtiedref : dbrow -> 'a dbfield -> 'a tiedref


-- 
Richard Jones, CTO Merjis Ltd.
Merjis - web marketing and technology - http://merjis.com
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